JP4621452B2 - Ultrasound endoscope and ultrasound endoscope apparatus - Google Patents

Description

  The present invention relates to an ultrasonic endoscope that can be inserted into a patient's body for medical diagnosis and to take an ultrasonic tomographic image, and an ultrasonic endoscope including such an ultrasonic endoscope. The present invention relates to a mirror device.

  In recent years, an ultrasonic endoscope has been used for medical diagnosis by inserting an ultrasonic tomogram into a patient's body. In such an ultrasonic endoscope, in general, a mechanical system that scans at a viewing angle of 360 ° by mechanically rotating an array including a plurality of ultrasonic transducers (ultrasonic transducers) that transmit and receive ultrasonic waves. A radial scanning method is employed.

  However, according to this mechanical radial scanning method, the acoustic ray density and scanning are compared with a scanning method in which a scanning angle of 90 ° is scanned using a convex-type ultrasonic transducer array in an extracorporeal ultrasonic imaging apparatus. When conditions such as depth are made the same, in order to perform scanning with a wide viewing angle, there is a problem that the scanning time (frame period) for obtaining an image of one frame becomes long and the frame rate decreases. .

  On the other hand, an electronic radial scanning method that performs scanning with a viewing angle of 360 ° by electronic scanning has been proposed. For example, the following Non-Patent Document 1 includes the results of studying the usefulness and problems of an electronic radial type ultrasonic endoscope based on the experience of using the electronic radial type ultrasonic endoscope for various digestive diseases. Are listed.

  Further, in Patent Document 1 below, when forming a flexible substrate in which a plurality of ultrasonic transducers are arranged in a cylindrical shape, the interval between the ultrasonic transducers at the joint portion of the flexible substrate is set to each of the intervals. A drive element switching circuit for driving the ultrasonic transducer adjacent to the interval to scan at the interval position between the ultrasonic transducers at the joint portion, and an integral multiple of the arrangement interval of the transducers; An electronic radial ultrasonic beam apparatus having improved resolution by providing a delay line is disclosed.

  However, even in an ultrasonic endoscope using the electronic radial scanning method, when a B-mode ultrasonic tomographic image having a viewing angle of 360 ° is to be taken, a plurality of ultrasonic transformers to be used are used as shown in FIG. It is necessary to sequentially transmit ultrasonic beams (sound rays) SL1 to SL360 while changing the position of the deuser along the circumferential direction. For this reason, the frame period T shown in FIG. 11A is about four times that of scanning using a convex ultrasonic transducer array with a viewing angle of 90 °, and the frame rate is about 1. / 4.

Furthermore, when blood flow information is obtained by the Doppler method in an electronic radial type ultrasonic endoscope, a plurality of pulses are sequentially transmitted in the same direction in order to improve the S / N ratio of minute blood flow information. Is done. For example, as shown in FIG. 11D, four ultrasonic beams SL1-1 to SL1-4 are sequentially transmitted in the first direction, this is repeated while changing the transmission direction, and finally the 360th direction. The four ultrasonic beams SL360-1 to SL360-4 are sequentially transmitted. In this case, the frame period is four times (4T) as shown in (c) of FIG. 11 as compared with the case where the B-mode ultrasonic tomographic image shown in (a) and (b) of FIG. Thus, the frame rate is reduced to about 1/4.
Junichi Takeda et al., “Current Status of Electronic Radial Ultrasound Endoscopy for Gastrointestinal Diseases”, Jpn J Med Ultrasonics, Vol. 31, Supplement, 77-C062, 2004 JP-A-2-134142 (page 2, upper right column, line 14 to lower left column, third line, page 4, lower right column, second line to line 10, line 3)

  Accordingly, in view of the above points, an object of the present invention is to improve the frame rate in electronic radial scanning in an ultrasonic endoscope that can be inserted into a patient's body and take an ultrasonic tomographic image. To do.

In order to solve the above-described problem, an ultrasonic endoscope according to one aspect of the present invention includes an ultrasonic transducer that includes a plurality of ultrasonic transducers each having a first electrode and a second electrode to transmit and receive ultrasonic waves. An ultrasonic transducer section, a plurality of first wires each connected to the first electrodes of the plurality of ultrasonic transducers, and a second electrode of the plurality of ultrasonic transducers that are not connected to each other. A plurality of second wirings connected to each other, a plurality of second wirings connected to each other between the plurality of second wirings and the ground potential, and each of the plurality of second wirings grounded or opened according to a control signal. And the ultrasonic transducer unit is configured to set the scanning angle region for each predetermined angle when a drive signal is selectively supplied via the plurality of first wirings and the plurality of second wirings. Multiple angle areas An ultrasonic beam of the same number in each of regions divided into, for scanning transmitting simultaneously at regular angular intervals.

An ultrasonic endoscope apparatus according to one aspect of the present invention includes an ultrasonic transducer unit including a plurality of ultrasonic transducers each having a first electrode and a second electrode and transmitting and receiving ultrasonic waves. A plurality of first wires each connected to a first electrode of the plurality of ultrasonic transducers and a second electrode of a plurality of ultrasonic transducers not connected to each other. An ultrasonic endoscope having a plurality of second wires, and a transmission means for generating a plurality of drive signals and supplying the plurality of drive signals to the ultrasonic transducer section via the plurality of first wires. A plurality of switch means connected between the plurality of second wirings and the ground potential , respectively, and grounding or opening each of the plurality of second wirings according to the control signal; and a scanning angle region at a predetermined angle Multiple corners per An ultrasonic beam of the same number in each of areas divided in the area, to perform a scan and transmit simultaneously at regular angular intervals, to control the transmission means, grounding one of the plurality of second wirings And a control means for supplying a control signal for controlling the others to the open state to the plurality of switch means.

  According to the present invention, it is possible to improve the frame rate by simultaneously transmitting the same number of ultrasonic beams at a certain angular interval in each region obtained by dividing the scanning angle region into a plurality of angle regions. In addition, when the angle interval of ultrasonic beams transmitted simultaneously is 90 °, the influence of crosstalk between a plurality of ultrasonic beams can be reduced, and the image quality of ultrasonic tomographic images can be made uniform. . Furthermore, by reducing the number of wires between the ultrasonic transducer unit and the main body device (ultrasound observation device), it is possible to reduce the size of the ultrasonic endoscope while reducing costs.

Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.
As shown in FIG. 1, an ultrasonic endoscope apparatus 1 according to an embodiment of the present invention is an ultrasonic observation apparatus capable of connecting an electronic radial type ultrasonic endoscope 2 and the ultrasonic endoscope 2. 3 and a display device 4 connected to the ultrasonic observation device 3.

  The ultrasonic observation apparatus 3 includes a console 11, a CPU (Central Processing Unit) 12, first and second switches SW1 and SW2, a transmission circuit 14, a reception circuit 15, a B-mode processing unit 16, A Doppler processing unit 17, a digital scan converter (DSC) 18, an image memory 19, and a digital / analog converter (D / A converter) 20 are included.

  As shown in FIG. 2, the ultrasonic endoscope 2 includes an insertion portion 31, an operation portion 32, a connection cord 33, and a universal cord 34.

  The insertion portion 31 of the ultrasonic endoscope 2 has an elongated flexible tubular shape so that it can be inserted into a patient's body. The operation unit 32 is provided at the proximal end of the insertion unit 31, is connected to the ultrasonic observation device 3 via the connection cord 33, and is connected to a light source device (not shown) via the universal cord 34. .

  The insertion portion 31 of the ultrasonic endoscope 2 is provided with an illumination window and an observation window. The illumination window is equipped with an illumination lens for emitting illumination light supplied from the light source device via the light guide. These constitute an illumination optical system. In addition, an objective lens is attached to the observation window, and an image guide input end or a solid-state imaging device such as a CCD camera is disposed at the imaging position of the objective lens. These constitute an observation optical system.

  FIG. 3 is an enlarged view showing the distal end of the ultrasonic endoscope 2 shown in FIG. An ultrasonic transducer section 40 in which a plurality of ultrasonic transducers are arranged on the circumference is provided at the distal end of the insertion section 31 of the ultrasonic endoscope 2. The ultrasonic transducer section 40 transmits an ultrasonic beam according to a plurality of drive signals supplied from the transmission circuit 14 of the ultrasonic observation apparatus 3 shown in FIG. 1 and receives an ultrasonic echo reflected from a target site or the like. The plurality of reception signals are output to the reception circuit 15 of the ultrasonic observation apparatus 3. In addition, a hole through which a treatment instrument inserted from a treatment instrument insertion port 35 provided in the operation section 32 is formed at the distal end of the insertion section 31 of the ultrasonic endoscope 2.

  As shown in FIG. 4, the ultrasonic transducer section 40 is configured by arranging 360 ultrasonic transducers T1 to T360 on the circumference. Here, the ultrasonic transducers T1 to T360 divide the scanning angle region with a viewing angle of 360 ° into four divided regions (first to fourth divided regions AR1 to AR4) every 90 °, and first to fourth. In order to perform radial scanning by transmitting four ultrasonic beams at the same timing in each of the divided areas AR1 to AR4, and to keep the interval between the four ultrasonic beams transmitted at the same timing at 90 °, the following It is divided into groups.

  The first group of ultrasonic transducers includes a first sub-region among the two sub-regions (first and second sub-regions SA1 and SA2) obtained by dividing the first divided region AR1 shown in FIG. 4 by 45 °. It is composed of 45 ultrasonic transducers T1 to T45 belonging to the area SA1. Therefore, the scanning range by the first group of ultrasonic transducers T1 to T45 is the range of the first sub-region SA1.

  The second group of ultrasonic transducers is composed of 45 ultrasonic transducers T46 to T90 belonging to the second sub group SA2. Therefore, the range of scanning by the second group of ultrasonic transducers T46 to T90 is the range of the second sub-region SA2.

  The third group of ultrasonic transducers includes a third sub-region among the two sub-regions (third and fourth sub-regions SA3 and SA4) obtained by dividing the second divided region AR2 shown in FIG. 4 by 45 °. It is composed of 45 ultrasonic transducers T91 to T135 belonging to the area SA3. Accordingly, the range of scanning by the third group of ultrasonic transducers T91 to T135 is the range of the third sub-region SA3.

  The fourth group of ultrasonic transducers is composed of 45 ultrasonic transducers T136 to T180 belonging to the fourth subgroup SA4. Therefore, the scanning range by the fourth group of ultrasonic transducers T136 to T180 is the range of the fourth sub-region SA4.

  The fifth group of ultrasonic transducers includes a fifth sub-region among the two sub-regions (fifth and sixth sub-regions SA5 and SA6) obtained by dividing the third divided region AR3 shown in FIG. 4 by 45 °. It consists of 45 ultrasonic transducers T181 to T225 belonging to the area SA5. Therefore, the range of scanning by the fifth group of ultrasonic transducers T181 to T225 is the range of the fifth sub-region SA5.

  The sixth group of ultrasonic transducers is composed of 45 ultrasonic transducers T226 to T270 belonging to the sixth subgroup SA6. Therefore, the range of scanning by the sixth group of ultrasonic transducers T226 to T270 is the range of the sixth sub-region SA6.

  The seventh group of ultrasonic transducers includes a seventh sub-region of the two sub-regions (seventh and eighth sub-regions SA7 and SA8) obtained by dividing the fourth divided region AR4 shown in FIG. 4 by 45 °. It comprises 45 ultrasonic transducers T271 to T315 belonging to the area SA7. Therefore, the scanning range by the seventh group of ultrasonic transducers T271 to T315 is the range of the seventh sub-region SA7.

  The eighth group of ultrasonic transducers includes 45 ultrasonic transducers T316 to T360 belonging to the eighth subgroup SA8. Therefore, the range of scanning by the eighth group of ultrasonic transducers T316 to T360 is the range of the eighth sub-region SA8.

  Each of the ultrasonic transducers T1 to T360 is configured by an ultrasonic vibrator in which a piezoelectric element such as PZT or PVDF is sandwiched between an individual electrode and a common electrode, and the individual electrode is in a state where the common electrode is grounded (grounded). When a drive signal is applied to the ultrasonic wave, ultrasonic waves are transmitted, and an ultrasonic echo reflected from a target site or the like is received to generate a reception signal on an individual electrode.

  As shown in FIG. 4, in each of the first to fourth divided regions AR <b> 1 to AR <b> 2, the individual electrodes of the two ultrasonic transducers positioned at an interval of 45 ° with respect to the circumferential direction of the ultrasonic transducer unit 40 are signal signals. The wirings EL1 to EL180 are electrically connected to the same one.

  For example, in the first divided region AR1, the individual electrodes of the ultrasonic transducer T1 in the first group and the ultrasonic waves in the second group that are located at 45 ° intervals with respect to the circumferential direction of the ultrasonic transducer section 40. The individual electrode of the transducer T46 is electrically connected to the signal wiring EL1. Similarly, the individual electrodes of the ultrasonic transducer T2 in the first group and the individual electrodes of the ultrasonic transducer T47 in the second group, which are positioned at 45 ° intervals with respect to the circumferential direction of the ultrasonic transducer unit 40, It is electrically connected to the signal wiring EL2.

  Further, in the second divided area AR2, the individual electrodes of the ultrasonic transducer T91 in the third group and the ultrasonic waves in the fourth group which are located at an interval of 45 ° with respect to the circumferential direction of the ultrasonic transducer section 40. The individual electrodes of the transducer T136 are electrically connected to the signal wiring EL46. Similarly, the individual electrodes of the ultrasonic transducer T92 in the third group and the individual electrodes of the ultrasonic transducer T137 in the fourth group, which are positioned at 45 ° intervals with respect to the circumferential direction of the ultrasonic transducer unit 40, It is electrically connected to the signal wiring EL47.

  On the other hand, the common electrodes of the ultrasonic transducers of the same group are electrically connected to the same one of the common electrode wirings G1 and G2, and at intervals of 90 ° with respect to the circumferential direction of the ultrasonic transducer section 40. The common electrodes of the plurality of groups of ultrasonic transducers located at the same position are also electrically connected to the same one of the common electrode wirings G1 and G2.

  That is, the ultrasonic transducers T1 to T45, T91 to T135, and T181 of the odd-numbered (first, third, fifth, and seventh) groups positioned at intervals of 90 ° with respect to the circumferential direction of the ultrasonic transducer unit 40. The common electrodes of T225 and T271 to T315 are electrically connected to the common electrode wiring G1. Further, the ultrasonic transducers T46 to T90, T136 to T180, and T226 of the even-numbered (second, fourth, sixth, and eighth) groups positioned at intervals of 90 ° with respect to the circumferential direction of the ultrasonic transducer unit 40. The common electrodes of T270 and T316 to T380 are electrically connected to the common electrode wiring G2.

  By wiring the individual electrodes and the common electrodes of the ultrasonic transducers T1 to T360 in this way, the number of wirings is the sum of the number 180 of the signal wirings EL1 to EL180 and the number 2 of the common electrode wirings G1 and G2. This is 182. As a result, the number of wires is about half that of the number of wires 361 (= 360 + 1) in the case where signal wires are wired to the individual electrodes of the ultrasonic transducers T1 to T360 and one common electrode wire is wired to the common electrode. Can be reduced.

  The signal wirings EL1 to EL180 are connected to the transmission circuit 14 and the reception circuit 15 of the ultrasonic observation apparatus 3 shown in FIG. 1 via the connection cord 33 shown in FIG. 2, and the common electrode wirings G1 and G2 are connected. Are connected to the first and second switches SW1 and SW2 of the ultrasonic observation apparatus 3 via the connection cord 23.

  The console 11 of the ultrasonic observation apparatus 3 shown in FIG. 1 starts / stops the ultrasonic imaging operation and mode switching (B mode or Doppler mode and frame) in the ultrasonic endoscope 2 based on the operation of the operator. A control signal A for controlling the rate priority mode or sensitivity priority mode is output to the CPU 12.

  The CPU 12 generates first and second switch control signals B1 and B2 for controlling on / off of the first and second switches SW1 and SW2 based on the control signal A input from the console 11. These signals are output to the first and second switches SW1 and SW2, respectively. Further, the CPU 12 outputs a transmission circuit control signal A 1 for controlling the operation of the transmission circuit 14 to the transmission circuit 14 and outputs a reception circuit control signal A 2 for controlling the operation of the reception circuit 15 to the reception circuit 15. To do.

  The first and second switches SW1 and SW2 are turned on / off based on the first and second switch control signals B1 and B2 input from the CPU 12. When the first and second switches SW1 and SW2 are turned on, the common electrode lines G1 and G2 are grounded. When the first and second switches SW1 and SW2 are turned off, the common electrode lines G1 and G2 are opened. Since the ultrasonic transducer operates only when the common electrode is grounded, the ultrasonic transducers T1 to T360 are divided into the odd-numbered (first, third, fifth, and seventh) groups and the even-numbered (second, The fourth, sixth, and eighth) groups can be operated separately.

  The transmission circuit 14 generates a plurality of drive signals based on the transmission circuit control signal A1, and outputs these drive signals onto the signal wirings EL1 to EL180. In accordance with these drive signals, ultrasonic waves are transmitted from a group of ultrasonic transducers whose common electrodes are grounded.

  On the other hand, the reception circuit 15 performs A / D conversion after amplifying a reception signal input from the group of ultrasonic transducers whose common electrodes are grounded via the signal wirings EL1 to EL180 with a predetermined amplification degree. Thus, the amplified received signal is converted into a digital received signal. Further, the reception circuit 15 performs processing such as phase matching on the digital reception signal to perform reception focus processing, thereby forming sound ray data in which the focus of the ultrasonic echo is narrowed down.

  The B-mode processing unit 16 performs an envelope detection process on the sound ray data formed by the receiving circuit 15 after correcting the attenuation according to the depth according to the depth of the reflection position of the ultrasonic wave. Data is generated.

  Based on the sound ray data formed by the receiving circuit 15, the Doppler processing unit 17 removes a high frequency component from the reception signal subjected to the reception focus process, and performs quadrature detection processing on the reception signal. Further, the Doppler processing unit 17 removes unnecessary clutter components caused by fluctuations in specular echoes such as blood vessel walls and heart walls from the received signal subjected to quadrature detection. In this way, Doppler image data in which only the reflection component from the bloodstream is extracted is generated.

  The DSC 18 is obtained by scanning the B-mode image data generated by the B-mode processing unit 16 or the Doppler image data generated by the Doppler processing unit 17 by a scanning method different from a normal television signal scanning method. Therefore, this data is converted into normal image data (raster conversion). The image memory 19 stores the image data generated by the DSC 18. The D / A converter 20 converts the digital image data read from the image memory 19 into an analog image signal and outputs the analog image signal to the display device 4. As a result, an ultrasonic tomographic image captured by the ultrasonic endoscope 2 is displayed on the display device 4.

Next, the operation of the ultrasonic endoscope apparatus 1 according to this embodiment will be described.
When an ultrasonic tomographic image is taken using the ultrasonic endoscope 2 shown in FIG. 2, the operator emits light from a light source connected to one end of the universal cord 34 and is applied to the distal end portion of the insertion portion 31. The illumination light is emitted from the provided illumination window into the patient's body, and the insertion portion 31 of the ultrasonic endoscope 2 is inserted into the patient's body while observing the insertion state from the observation window.

  First, the operation of the ultrasonic endoscope apparatus when taking a B-mode image will be described. When the insertion unit 31 reaches the target position, the operator operates the console 11 (FIG. 1) to start the operation of the ultrasonic endoscope 2 and to send a control signal A for designating the B mode to the console. 11 to CPU 12 for output.

  Based on this control signal A, the CPU 12 outputs to the transmission circuit 14 a transmission circuit control signal A1 that instructs the start of the operation of the transmission circuit 14 and the generation of the drive signal for the B mode. In addition, the CPU 12 outputs a reception circuit control signal A <b> 2 that instructs the start of the operation of the reception circuit 15 to the reception circuit 15.

Further, the CPU 12 outputs a first switch control signal B1 for turning on the first switch SW1 to the first switch SW1. When the first switch SW1 is turned on, the common electrode line G1 is grounded, and the ultrasonic transducers T1 to T45, T91 to T135 of the odd-numbered (first, third, fifth, and seventh) groups shown in FIG. , T181 to T225 and T271 to T315 are grounded.

The transmission circuit 14 is connected to the odd-numbered (first, third, fifth, and seventh) groups of ultrasonic transducers T1 to T45, T91 to T135, T181 to T225, and T271 to T315 via the signal wirings EL1 to EL180. A plurality of drive signals (in this embodiment, referred to as pulse signals) supplied to the individual electrodes are generated. At this time, the transmission circuit 14 uses three ultrasonic transducers to form one ultrasonic beam, so that the four ultrasonic beams are transmitted at the same timing from 90 ° apart from each other. In addition, these drive signals are generated.

  For example, as shown in FIG. 5, an ultrasonic beam (sound ray) SL1 ((b) in FIG. 5) is transmitted from the ultrasonic transducers T1 to T3 in the first group in the divided area AR1, and in the divided area AR2. The ultrasonic beam SL91 (FIG. 5C) is transmitted from the ultrasonic transducers T91 to T93 in the third group, and the ultrasonic beam SL181 is transmitted from the ultrasonic transducers T181 to T183 in the fifth group in the divided area AR3. ((D) in FIG. 5) are transmitted, and in the divided area AR4, the ultrasonic beam SL271 ((e) in FIG. 5) is transmitted from the ultrasonic transducers T271 to T273 in the seventh group. A drive pulse signal for driving the ultrasonic transducer is generated.

  A plurality of reception signals obtained by receiving ultrasonic echoes generated by reflection of these ultrasonic beams from the subject are output to the reception circuit 15 via the signal wirings EL1 to EL180 to form sound ray data. After the B-mode image data is generated in the B-mode processing unit 16, the data is raster-converted in the DSC 18 to generate image data. The image data is stored in the image memory 19.

When scanning by the ultrasonic transducers T1 to T45, T91 to T135, T181 to T225, and T271 to T315 of the odd-numbered (first, third, fifth, and seventh) groups ends, the CPU 12 switches the first switch SW1. The first switch control signal B1 for turning off the first switch SW1 is output to the first switch SW1, and the second switch control signal B2 for turning on the second switch SW2 is output to the second switch SW2. Thereby, since the common electrode wiring G2 is grounded, the ultrasonic transducers T46 to T90, T136 to T180, T226 to T270, and T316 to T360 of the even-numbered (second, fourth, sixth, and eighth) groups . The common electrode is grounded.

As in the case of the odd-numbered group of ultrasonic transducers, the transmission circuit 14 transmits the even-numbered (second, fourth, sixth, and eighth) groups of ultrasonic transducers T46 to T46 through the signal wirings EL1 to EL180. A plurality of drive pulse signals supplied to the individual electrodes T90, T136 to T180, T226 to T270, and T316 to T360, respectively, are generated.

  A plurality of reception signals obtained by receiving ultrasonic echoes generated by reflection of these ultrasonic beams from the subject are output to the reception circuit 15 via the signal wirings EL1 to EL180 to form sound ray data. After the B-mode image data is generated in the B-mode processing unit 16, the data is raster-converted in the DSC 18 to generate image data. The image data is stored in the image memory 19.

By the above operation, the odd-numbered and even-numbered groups of ultrasonic transducers are alternately used to perform the convex scanning of each divided region, thereby performing the radial scanning in the scanning angle range of 360 ° in total . The scanning angle range is not limited to 360 °, and may be 180 ° or other values. Image data read from the image memory 19 is converted into an analog image signal by the D / A converter 20 and output to the display device 4. As a result, a B-mode ultrasonic tomogram is displayed on the display device 4.

  According to the ultrasonic endoscope apparatus according to the present embodiment, since ultrasonic beams are transmitted in four directions at the same timing, in the B mode, a diagram in the case of transmitting ultrasonic beams one by one as in the prior art. Compared with the frame period T shown in FIG. 11 (a), the frame period is set to 1/4 (that is, T / 4) and the frame rate is quadrupled as shown in FIG. 5 (a). Can do. In addition, since the angular interval of the four ultrasonic beams transmitted at the same timing is 90 °, it is possible to hardly generate crosstalk due to the simultaneous transmission of a plurality of ultrasonic beams.

Note that near the boundary of the subregion SA1~SA 8 (i.e., before and after switching of groups of ultrasonic transducers by the first and second switches SW1 and SW2) in the next sub-region in order to transmit an ultrasonic beam Since the ultrasonic transducer cannot be used, the ultrasonic beam becomes uneven.

  Therefore, for example, after transmitting the ultrasonic beam SL45, the delay of the drive pulse signal supplied to the individual electrodes of the ultrasonic transducers T43, T44, and T45 in the first group used to transmit the ultrasonic beam SL45. Sector scanning is performed by controlling the amount and steering the ultrasonic beam, and as shown in FIG. 8, the ultrasonic beam SL45 ′ is transmitted to the second sub-region SA2 side from the ultrasonic beam SL45.

  Thereafter, before transmitting the ultrasonic beam SL46 using the ultrasonic transducers T46, T47, T48 in the second group, the drive pulse signals supplied to the individual electrodes of these ultrasonic transducers T46, T47, T48 are transmitted. Sector scanning is performed by controlling the delay amount to steer the ultrasonic beam, and as shown in FIG. 8, the ultrasonic beam SL46 ′ is transmitted to the first sub-region SA1 side from the ultrasonic beam SL46. As a result, it is possible to reduce the unevenness of the ultrasonic beam at the boundary between the first sub-region SA1 and the second sub-region SA2.

  The ultrasonic beam is also applied to the boundary between the third and fourth sub-regions SA3 and SA4, the boundary between the fifth and sixth sub-regions SA5 and SA6, and the boundary between the seventh and eighth sub-regions SA7 and SA8. Simultaneously performing sector scanning for steering the ultrasonic beams SL135 ′, SL225 ′, and SL315 ′ during the sector scanning for steering the SL45 ′, and performing ultrasonic scanning SL136 ′, for the sector scanning for steering the ultrasonic beam SL46 ′, Sector scanning for steering SL 226 ′ and SL 316 ′ is performed at the same time to prevent a decrease in frame rate due to an increase in the number of ultrasonic beams.

  Next, the operation of the ultrasonic endoscope apparatus when taking a Doppler mode image with priority on the frame rate will be described. The operator operates the console 11 (FIG. 1) to start the operation of the ultrasonic endoscope 2 and output a control signal A for instructing the frame rate priority Doppler mode from the console 11 to the CPU 12. .

  Based on the control signal A, the CPU 12 outputs to the transmission circuit 14 a transmission circuit control signal A1 that instructs the start of the operation of the transmission circuit 14 and the generation of the drive signal for the frame rate priority Doppler mode. In addition, the CPU 12 outputs a reception circuit control signal A <b> 2 that instructs the start of the operation of the reception circuit 15 to the reception circuit 15. In the frame rate priority Doppler mode, the transmission circuit 14 generates a drive pulse signal so that four ultrasonic beams (pulses) are continuously transmitted four times in each of the four directions.

  For example, as shown in FIG. 6, in the divided area AR1, four ultrasonic beams (sound rays) SL1-1 to SL1-4 (sound rays) SL1-1 to SL1-4 ((b of FIG. 6) are continuous from the ultrasonic transducers T1 to T3 in the first group. )) Is transmitted, and four ultrasonic beams SL91-1 to SL91-4 ((c) in FIG. 6) are transmitted from the ultrasonic transducers T91 to T93 in the third group in the divided area AR2, and are divided. Four ultrasonic beams SL181-1 to SL181-4 (FIG. 6D) are transmitted from the ultrasonic transducers T181 to T183 in the fifth group in the area AR3, and the seventh group in the divided area AR4. Of four ultrasonic beams SL271-1 to SL271-4 (FIG. 6 (e)). ) As is transmitted, the driving pulse signal for driving the ultrasonic transducers are generated.

  A plurality of reception signals obtained by receiving ultrasonic echoes generated by reflection of these ultrasonic beams from the subject are output to the reception circuit 15 via the signal wirings EL1 to EL180 to form sound ray data. Then, after being converted into Doppler image data in the Doppler processing unit 17, this data is raster-converted by the DSC 18 to generate image data. The image data is stored in the image memory 19.

As described above, each divided region included in the scanning angle range is subjected to convex scanning, whereby radial scanning is performed on the entire scanning angle range. Furthermore, as in the first embodiment, in the vicinity of the boundary of the subregion SA1～SA 8 is a sector scan for steering the ultrasound beam is carried out. The image data stored in the image memory 19 is read out, converted into an analog image signal by the D / A converter 20, and output to the display device 4. Thereby, a frame rate priority Doppler image is displayed on the display device 4.

  According to the frame rate priority Doppler mode, four ultrasonic beams are repeatedly transmitted four times in four directions, so that one ultrasonic beam is continuously transmitted four times as in the prior art. Compared with the frame period 4T shown in (b), as shown in (a) of FIG. 6, the frame period can be reduced to ¼ (that is, T) and the frame rate can be quadrupled.

  For example, when obtaining blood flow information in a place with a large pulsation, the frame rate priority Doppler mode in which the number of repetitions of transmitting ultrasonic beams in the same direction is reduced is better. When obtaining blood flow information in a small area, it is better to use the Doppler mode that gives priority to sensitivity, in which the number of repetitions for repeatedly transmitting ultrasonic beams in the same direction is increased.

  When taking a Doppler image in the sensitivity priority Doppler mode, the operator operates the console 11 (FIG. 1) to start the operation of the ultrasonic endoscope 2 and instruct the sensitivity priority Doppler mode. The control signal A is output from the console 11 to the CPU 12.

  Based on this control signal A, the CPU 12 outputs to the transmission circuit 14 a transmission circuit control signal A1 that instructs the start of the operation of the transmission circuit 14 and the generation of a drive signal for Doppler mode giving priority to sensitivity. In addition, the CPU 12 outputs a reception circuit control signal A <b> 2 that instructs the start of the operation of the reception circuit 15 to the reception circuit 15. In the sensitivity priority Doppler mode, the transmission circuit 14 generates a drive pulse signal so that four ultrasonic beams (pulses) are continuously transmitted 16 times in each of four directions.

  For example, as shown in FIG. 7, in the divided area AR1, 16 ultrasonic beams (sound rays) SL1-1 to SL1-16 (sound rays) SL1-1 (SL in FIG. 7) that are continuous from the ultrasonic transducers T1 to T3 in the first group. b)) is transmitted, and in the divided area AR2, 16 ultrasonic beams SL91-1 to SL91-16 (FIG. 7C) are transmitted from the ultrasonic transducers T91 to T93 in the third group. In the divided area AR3, 16 ultrasonic beams SL181-1 to SL181-16 (FIG. 7 (d)) continuous from the ultrasonic transducers T181 to T183 in the fifth group are transmitted, and in the divided area AR4, 16 ultrasonic beams SL271-1 to SL271-continuous from the ultrasonic transducers T271 to T273 in seven groups. 6 as (in FIG. 7 (e)) is transmitted, the driving pulse signal for driving the ultrasonic transducers are generated.

Thereafter, a Doppler image with improved sensitivity is displayed on the display device 4 by the same operation as in the frame rate priority Doppler mode described above.
According to the Doppler mode that gives priority to sensitivity, four ultrasonic beams are transmitted 16 times repeatedly in four directions. Compared to the frame period 16T in which one ultrasonic beam is repeatedly transmitted 16 times as in the prior art. Then, as shown in FIG. 7A, the frame period can be reduced to 1/4 (that is, 4T) and the frame rate can be quadrupled.

  For frame priority and sensitivity priority in Doppler mode, for example, the operator can select one of 14 combinations of sensitivity s and frame rate f (= 1 / T) as shown in FIG. A slide switch 50 as shown in FIG. 10 may be provided on the console 11 in FIG. As a result, the operator can finely select the sensitivity s and the frame rate f in accordance with the application, thereby improving usability.

  In the above embodiment, radial scanning is performed while transmitting one ultrasonic beam at a time in each of the first to fourth divided areas AR1 to AR4. Radial scanning may be performed while transmitting a sound beam at the same timing.

  Further, although the 360 ° scanning angle region is divided into four divided regions every 90 °, the angle for dividing the scanning angle region may be other than 90 °. For example, a scanning angle region of 360 ° may be divided into two divided regions every 180 °, and radial scanning may be performed while transmitting a predetermined number of ultrasonic beams at the same timing in each divided region.

  Further, each of the first to fourth divided areas AR1 to AR4 is divided into sub-areas SA1 to SA8 by 45 degrees, and the ultrasonic transducers are grouped for each of the sub-areas SA1 to SA8. The angle divided into the sub-regions may be other than 45 °.

  For example, each of the first to fourth divided areas AR1 to AR4 may be divided by 30 ° into sub-areas SA1 to SA12 to form 12 ultrasonic transducer groups. In this case, the number of signal wirings is 120, and in each of the first to fourth divided regions AR1 to AR4, three ultrasonic transducers separated by every 30 ° out of the plurality of ultrasonic transducers are individually provided. The electrodes are electrically connected to the same signal wiring.

  In this case, the number of common electrode lines G is three, the common electrodes of the ultrasonic transducers in the same group are electrically connected to the same common electrode lines, and the circumference of the ultrasonic transducer unit 40 is The common electrodes of the plurality of groups of ultrasonic transducers positioned at 90 ° intervals with respect to the direction are electrically connected to the same common electrode wiring. Accordingly, the ultrasonic observation apparatus 3 shown in FIG. 1 is provided with three switches, and any one of the three switches is turned on according to the three switch control signals supplied from the CPU 12.

  In the above embodiment, the electronic radial type ultrasonic endoscope has been described. However, for example, a convex type ultrasonic endoscope in which 180 ultrasonic transducers are arranged in a semicircular shape is also used for scanning omnidirectional scanning. The 180 ° region is divided into two divided regions every 90 °, and scanning is performed by transmitting ultrasonic beams one by one and at the same timing in each divided region. Can be applied.

Further, the first and second switches SW1 and SW2 shown in FIG. 1 are provided in the ultrasonic observation apparatus 3, but may be provided in the ultrasonic endoscope 2.
Further, the start / stop of the ultrasonic imaging operation in the ultrasonic endoscope 2 is controlled and the control signal A for instructing the mode is output from the console 11. For example, the operation of the ultrasonic endoscope 2 is performed. A button for generating the control signal A may be provided in the unit 32 so that the control signal A is output from the operation unit 32 to the CPU 12.

  The present invention relates to an ultrasonic endoscope that can be inserted into a body and photograph an ultrasonic tomographic image for medical diagnosis, and an ultrasonic endoscope apparatus including such an ultrasonic endoscope. Can be used.

1 is a diagram showing a configuration of an ultrasonic endoscope apparatus 1 according to an embodiment of the present invention. It is a figure which shows the structure of the ultrasonic endoscope 2 shown in FIG. FIG. 3 is an enlarged view showing a distal end of the ultrasonic endoscope 2 shown in FIG. 2. It is a figure which shows the structure of the ultrasonic transducer part 40 shown in FIG. It is a figure for demonstrating the frame rate when the ultrasound endoscope 2 shown in FIG. 1 is driven in B mode. It is a figure for demonstrating the frame rate when the ultrasonic endoscope 2 shown in FIG. 1 is driven by the Doppler mode of the frame rate priority. It is a figure for demonstrating the frame rate when the ultrasonic endoscope 2 shown in FIG. 1 is driven by the Doppler mode of sensitivity priority. It is a figure for demonstrating the steering operation in the boundary of a sub area | region. It is a figure which shows an example of the combination of a frame rate and a sensitivity. It is a figure which shows the slide switch for selecting one of the combinations of a frame rate and a sensitivity. It is a figure for demonstrating the frame rate in the conventional ultrasonic endoscope.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ultrasonic endoscope apparatus 2 Ultrasonic endoscope 3 Ultrasonic observation apparatus 4 Display apparatus 11 Console 12 CPU
14 Transmission Circuit 15 Reception Circuit 16 B Mode Processing Unit 17 Doppler Processing Unit 18 DSC
19 Image Memory 20 D / A Converter 31 Insertion Unit 32 Operation Unit 33 Connection Code 34 Universal Code 35 Treatment Instrument Insertion Port 40 Ultrasonic Transducer Unit 50 Slide Switch EL1 to EL180 Signal Wiring G1, G2 Common Electrode Wiring SW1, SW2 Switch T1 ~ T360 Ultrasonic transducer

Claims (11)

An ultrasonic transducer section including a plurality of ultrasonic transducers each having a first electrode and a second electrode for transmitting and receiving ultrasonic waves;
A plurality of first wires each connected to a first electrode of the plurality of ultrasonic transducers;
A plurality of second wirings each connected to a second electrode of a plurality of ultrasonic transducers where the first electrodes are not connected to each other;
A plurality of switch means connected between the plurality of second wirings and a ground potential , respectively, and grounding or releasing each of the plurality of second wirings according to a control signal;
And when the ultrasonic transducer section is selectively supplied with a drive signal via the plurality of first wirings and the plurality of second wirings, a scanning angle region is set for each predetermined angle. An ultrasonic endoscope that performs scanning by simultaneously transmitting the same number of ultrasonic beams at a predetermined angular interval in each of the regions divided into a plurality of angular regions. When each of the plurality of first wirings divides each of the plurality of angle regions into a plurality of subregions for each second predetermined angle, the second predetermined angle in the plurality of subregions. Connected to the first electrodes of a plurality of ultrasonic transducers located in each
When each of the plurality of second wirings groups the plurality of ultrasonic transducers for each of the sub-regions, each of the plurality of second wirings serves as a second electrode of the plurality of groups of ultrasonic transducers positioned at each predetermined angle. It is connected,
The ultrasonic endoscope according to claim 1.   When the predetermined angle is 90 ° and the ultrasonic transducer unit is selectively supplied with a drive signal via the plurality of first wires and the plurality of second wires, The ultrasonic endoscope according to claim 2, wherein the scanning is performed by simultaneously transmitting acoustic beams at 90 ° intervals. An ultrasonic transducer unit including a plurality of ultrasonic transducers each having a first electrode and a second electrode to transmit and receive ultrasonic waves, and a plurality of each connected to the first electrodes of the plurality of ultrasonic transducers An ultrasonic endoscope having a first wiring and a plurality of second wirings each connected to a second electrode of a plurality of ultrasonic transducers in which the first electrodes are not connected to each other;
Transmitting means for generating a plurality of drive signals and supplying the plurality of drive signals to the ultrasonic transducer section via the plurality of first wires;
A plurality of switch means connected between the plurality of second wirings and a ground potential , respectively, and grounding or releasing each of the plurality of second wirings according to a control signal;
Controlling the transmitting means so as to perform scanning by simultaneously transmitting the same number of ultrasonic beams at a predetermined angular interval in each region obtained by dividing the scanning angle region into a plurality of angle regions at predetermined angles; Control means for supplying a control signal to the plurality of switch means for controlling to ground one of the plurality of second wirings and to open the other ;
An ultrasonic endoscope apparatus comprising:   The transmission means transmits the scanning angle region into a plurality of angle regions for each predetermined angle and a convex scan for selectively driving the plurality of ultrasonic transducers and a predetermined number of ultrasonic transducers. The ultrasonic endoscope apparatus according to claim 4, wherein a drive signal is selectively supplied to the ultrasonic transducer unit so as to be combined with sector scanning for steering an ultrasonic beam formed by the ultrasonic wave.   The transmitting means selectively outputs an ultrasonic beam formed by ultrasonic waves transmitted from a predetermined number of ultrasonic transducers in a convex scan that selectively drives the plurality of ultrasonic transducers and in a non-scannable region of the convex scan. The ultrasonic endoscope apparatus according to claim 5, wherein a drive signal is selectively supplied to the ultrasonic transducer unit so as to be combined with a sector scan to be steered. When each of the plurality of first wirings divides each of the plurality of angle regions into a plurality of subregions for each second predetermined angle, the second predetermined angle in the plurality of subregions. Connected to the first electrodes of a plurality of ultrasonic transducers located in each
When each of the plurality of second wirings groups the plurality of ultrasonic transducers for each of the sub-regions, each of the plurality of second wirings serves as a second electrode of the plurality of groups of ultrasonic transducers positioned at each predetermined angle. It is connected,
The ultrasonic endoscope apparatus according to any one of claims 4 to 6.   When the predetermined angle is 90 ° and the ultrasonic transducer unit is selectively supplied with a drive signal via the plurality of first wires and the plurality of second wires, The ultrasonic endoscope apparatus according to claim 7, wherein scanning is performed by simultaneously transmitting acoustic beams at 90 ° intervals.   In Doppler mode that transmits multiple ultrasonic pulses continuously in each transmission direction, frame rate priority mode that prioritizes frame rate by reducing the number of continuous ultrasonic pulses and the number of continuous ultrasonic pulses The ultrasonic endoscope apparatus according to any one of claims 4 to 8, further comprising mode switching means for switching between a sensitivity priority mode that gives priority to sensitivity more than in the rate priority mode.   The ultrasonic endoscope apparatus according to any one of claims 4 to 9, wherein the plurality of switch means are provided in the ultrasonic endoscope.   The ultrasonic endoscope apparatus according to claim 9, wherein the mode switching unit is provided in the ultrasonic endoscope.

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